Final answer:
One formula unit of Ba(OH)2 contains 5 atoms, including 1 barium atom, 2 oxygen atoms, and 2 hydrogen atoms. This composition is important when considering reaction stoichiometry, as different elements and compounds will react in specific ratios based on the number of atoms or moles present.
Step-by-step explanation:
The formula Ba(OH)2 represents barium hydroxide. In barium hydroxide, there is one barium (Ba) atom, two oxygen (O) atoms, and two hydrogen (H) atoms. This can be determined by looking at the chemical formula, where Ba is the symbol for a single barium atom, and the (OH)2 part indicates that there are two hydroxide ions, each consisting of one oxygen and one hydrogen. Therefore, we have:
- 1 x Ba = 1 barium atom
- 2 x O = 2 oxygen atoms
- 2 x H = 2 hydrogen atoms
In total, there are 5 atoms present in one formula unit of Ba(OH)2. These include 1 barium atom, 2 oxygen atoms, and 2 hydrogen atoms.